Various apparatus have been proposed for controlling the rotational movement of one rotary means relative to the rotational movement of a second rotary means. Many of these apparatus have been developed for use with toroidal rotary internal combustion engines. These engines have rotary pistons orbiting in an annular cylinder. Such engines have been called "cat-and-mouse" type engines because the pistons are required to alternately approach and recede from each other, comparable to the way a cat chases a mouse, so that the volume of the chambers formed between the pistons sequentially varies during the course of the intake, compression, combustion, and exhaust phasing of such engines. To accomplish this cat-and-mouse movement, at least one piston assembly must move at a non-uniform varying speed with respect to the speed of the other piston assembly during each revolution. This is accomplished by a transfer mechanism between the shafts of the two rotary piston assemblies.
One known device comprises a planetary drive in conjunction with a crank and connecting rod arrangement. A planet carrier supporting a single planet gear and a crank is rigidly connected to one rotary means. The planet gear meshes with a stationary sun gear while another crank, rigidly connected to a second rotary means, is linked by a connecting rod, through the planet gear crank and shaft, to the planet carrier. Counterweights are applied to both cranks and to the planet carrier. The combination of gears and connecting rods result in a relatively frail mechanism with the additional disadvantage of the requirement for careful balancing of the counterweights, and the assembly takes up considerable space.
Another known construction comprises a first rotary means which causes a pivotally mounted slide block to rotate about a circular path. A connecting rod slides in the slide block. One end of the connecting rod is pivotally joined to a crank mounted on a second rotary means. The other end of the connecting rod has a roller which follows a trough-like non-circular path. While this construction has no gears, it remains relatively complex and frail, and it also requires considerable space.
It is also known to use a cam and roller arrangement wherein two diametrically opposed rollers are mounted upon each of two rotary means. The roller pair associated with a given rotary means coacts with a companion asymmetrically configured cam. The two cams are fixedly mounted in a spaced apart relationship on a single shaft. One cam is axially rotated 180 degrees with respect to the other so that their asymmetrical configurations are in diametric opposition. The configuration of each cam is such as to alternately engage with and then disengage from its associated rotary means so as to momentarily bring one rotary means to a stop while allowing the other rotary means to continue to rotate, and visa versa. This construction has the disadvantage of causing the entire rotating mass associated with each rotary means to be alternately brought to rest and then accelerated.